Optical recording device and optical recording method

1. An optical recording device comprising: a light source, generating a signal beam and a reference beam radiating with the same optical axis from the same direction; a light-converging optical system, converging recording light that includes the signal beam and the reference beam to at least one optical recording layer of a transmission optical recording medium; a moving unit, moving a convergence position where the recording light is converged by the light-converging optical system relative to the transmission optical recording medium, such movement being relative movement in an in-plane direction of the transmission optical recording medium as well as relative movement in the optical axis direction; a detection unit, detecting the amount of movement from a convergence position reference position in the optical axis direction; and an acquisition unit, deriving, for each of a plurality of convergence positions in the optical axis direction, a cumulative exposure amount within a plane that includes the convergence position moved by the movement amount, the derivation of the cumulative exposure amount being based on the recording sensitivity of the optical recording layer and on the movement amount of the convergence position detected by the detection unit, and apportioning the cumulative exposure amount across all the pages of in-plane recording to acquire the light exposure amount for each page, wherein interference fringes from the recording light are shift multi-recorded as a plurality of pages of holograms within a plurality of planes corresponding to the plurality of convergence positions, based on the light exposure amount of each page acquired, by the acquisition unit, for each of the convergence positions.

2. The optical recording device according to claim 1 , wherein shift multi-recording is performed within each of the plurality of planes corresponding to the plurality of convergence positions in sequence from the side on which the recording light is incident to the transmission optical recording medium.

3. The optical recording device according to claim 1 , wherein shift multi-recording is performed within each of the plurality of planes corresponding to the plurality of convergence positions in sequence from the optical recording layer with the highest recording sensitivity when a plurality of optical recording layers with different recording sensitivities are provided in the transmission optical recording medium.

4. The optical recording device according to claim 1 , wherein: when a plurality of optical recording layers with different recording sensitivities are provided in the transmission optical recording medium, the optical recording layers are disposed in sequence from the optical recording layer with the highest recording sensitivity from the recording light incident side where the recording light is incident to the transmission optical recording medium; and shift multi-recording is performed within each of the plurality of planes corresponding to the plurality of convergence positions in sequence from the side on which the recording light is incident to the transmission optical recording medium.

5. An optical recording method comprising: making recording light, which includes a signal beam and a reference beam radiated coaxially from the same direction, converge to at least one optical recording layer of a transmission optical recording medium using a light-converging optical system; moving a convergence position where the recording light is converged by the light-converging optical system relative to the transmission optical recording medium, such movement being relative movement in an in-plane direction of the transmission optical recording medium as well as relative movement in the optical axis direction; detecting the amount of movement from a convergence position reference position in the optical axis direction; and deriving, for each of a plurality of convergence positions in the optical axis direction, a cumulative exposure amount within a plane including the convergence position moved by the movement amount, the derivation of the cumulative exposure amount being based on the recording sensitivity of the optical recording layer and on the detected movement amount of the convergence position, apportioning the cumulative exposure amount across all the pages of in-plane recording to acquire the light exposure amount for each page, wherein interference fringes from the recording light are shift multi-recorded as a plurality of pages of holograms within a plurality of planes corresponding to the plurality of convergence positions, based on the light exposure amount of each page acquired for each of the convergence positions.

6. The optical recording method according to claim 5 , wherein shift multi-recording is performed within each of the plurality of planes corresponding to the plurality of convergence positions in sequence from the side on which the recording light is incident to the transmission optical recording medium.

7. The optical recording method according to claim 5 , wherein shift multi-recording is performed within each of the plurality of planes corresponding to the plurality of convergence positions in sequence from the optical recording layer with the highest recording sensitivity when a plurality of optical recording layers with different recording sensitivities are provided in the transmission optical recording medium.

8. The optical recording method according to claim 5 , wherein: when a plurality of optical recording layers with different recording sensitivities are provided in the transmission optical recording medium, the optical recording layers are disposed in sequence from the optical recording layer with the highest recording sensitivity from the recording light incident side where the recording light is incident to the transmission optical recording medium; and shift multi-recording is performed within each of the plurality of planes corresponding to the plurality of convergence positions in sequence from the side on which the recording light is incident to the transmission optical recording medium.